Daniel Philippe
Well-known member
There is this abstract in the 125th Meeting of the American Ornithologists' Union (2007):
Phylogeography of the Tepui Brush Finch (Atlapetes personatus): Tepuis as islands.
GEORGE F. BARROWCLOUGH, JEFF G. GROTH and BARTEK JABLONSKI, Am. Mus. Nat. Hist., New York, NY.
The Tepui Brush Finch has a fragmented distribution in upper tropical and temperate vegetation on tepuis and similar geological structures in Venezuela and adjacent regions of Brazil and Guyana. Unsuitable habitats, such as tropical lowland forest and savannah grasslands, separate the populations. We sequenced 4 mitochondrial genes to determine the extent of isolation and genetic divergence between population samples. The finches were composed of 3 divergent genetic clades whose geographical distributions were concordant with major subspecies groups based on morphology; these represent 3 species. Gene flow between populations within the subspecies groups was essentially non-existent for samples more than 100 km apart. The geographical origin of the Tepui Brush Finch is uncertain due to heterogeneity of base composition in these mitochondrial genes.
And this one more recently (AOU/COS/SCO August 2008 meeting) http://www.pdxbirds08.org/files/pdx2008-abstracts.pdf :
PHYLOGEOGRAPHY OF THE TEPUI BRUSH-FINCH: NUCLEAR INTRONS VS. MTDNA
Lai, J. E., American Museum of Natural History, New York, USA, [email protected]
Barrowclough, G. F., American Museum of Natural History, New York, USA, [email protected]
Groth, J. G., American Museum of Natural History, New York, USA, [email protected]
The biogeographic and genetic structure of organisms endemic to the high elevation habitat islands (tepuis) of the Guiana Shield in southern Venezuela and adjacent areas of Brazil are poorly known. We continued our investigation of taxon limits in the Tepui Brush-Finch (Atlapetes personatus) species complex, adding nuclear DNA sequence data to our mitochondrial sequences. Phylogenetic trees and haplotype networks that result are generally congruent with prior mtDNA results, but show less resolution among tepuis. This is consistent with coalescence theory: signal from nuclear loci are a lagging indicator, relative to mtDNA, of vicariant events. Our new results support the previous finding that Tepui Brush-Finch populations are genetically independent units and the tepuis are acting like isolated islands for this taxon. These results suggest that nuclear sequences only make a modest additional contribution to mitochondrial phylogeographic signal
Anybody who knows the detailed segregation (subspecies groups) ?
Phylogeography of the Tepui Brush Finch (Atlapetes personatus): Tepuis as islands.
GEORGE F. BARROWCLOUGH, JEFF G. GROTH and BARTEK JABLONSKI, Am. Mus. Nat. Hist., New York, NY.
The Tepui Brush Finch has a fragmented distribution in upper tropical and temperate vegetation on tepuis and similar geological structures in Venezuela and adjacent regions of Brazil and Guyana. Unsuitable habitats, such as tropical lowland forest and savannah grasslands, separate the populations. We sequenced 4 mitochondrial genes to determine the extent of isolation and genetic divergence between population samples. The finches were composed of 3 divergent genetic clades whose geographical distributions were concordant with major subspecies groups based on morphology; these represent 3 species. Gene flow between populations within the subspecies groups was essentially non-existent for samples more than 100 km apart. The geographical origin of the Tepui Brush Finch is uncertain due to heterogeneity of base composition in these mitochondrial genes.
And this one more recently (AOU/COS/SCO August 2008 meeting) http://www.pdxbirds08.org/files/pdx2008-abstracts.pdf :
PHYLOGEOGRAPHY OF THE TEPUI BRUSH-FINCH: NUCLEAR INTRONS VS. MTDNA
Lai, J. E., American Museum of Natural History, New York, USA, [email protected]
Barrowclough, G. F., American Museum of Natural History, New York, USA, [email protected]
Groth, J. G., American Museum of Natural History, New York, USA, [email protected]
The biogeographic and genetic structure of organisms endemic to the high elevation habitat islands (tepuis) of the Guiana Shield in southern Venezuela and adjacent areas of Brazil are poorly known. We continued our investigation of taxon limits in the Tepui Brush-Finch (Atlapetes personatus) species complex, adding nuclear DNA sequence data to our mitochondrial sequences. Phylogenetic trees and haplotype networks that result are generally congruent with prior mtDNA results, but show less resolution among tepuis. This is consistent with coalescence theory: signal from nuclear loci are a lagging indicator, relative to mtDNA, of vicariant events. Our new results support the previous finding that Tepui Brush-Finch populations are genetically independent units and the tepuis are acting like isolated islands for this taxon. These results suggest that nuclear sequences only make a modest additional contribution to mitochondrial phylogeographic signal
Anybody who knows the detailed segregation (subspecies groups) ?
Last edited:
